<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <title>常用输出语句</title>
</head>

<body>
    <script type="text/javascript">
        alert('登陆成功！');
        console.log('控制台输出');
        document.write('在HTML文档中输出')
    </script>
</body>

</html>